问题 解答题
用简便方法计算(写出计算过程):
385+295+105;643-12-88;125×32;
8×48×125;4200÷6÷7;360÷45;
125×8+275×8;99×84;25×1-25.
答案

(1)385+295+105

=385+(295+105)

=385+400

=785;

(2)643-12-88

=643-(12+88)

=643-100

=543;

(3)125×32

=125×8×4

=1000×4

=4000;

(4)8×48×125

=8×125×48

=1000×48

=48000;

(5)4200÷6÷7

=4200÷(6×7)

=4200÷42

=100;

(6)360÷45

=360÷9÷5

=40÷5

=8;

(7)125×8+275×8

=(125+275)×8

=400×8

=3200;

(8)99×84

=1100×84-1×84

=8400-84

=8316;

(9)25×1-25

=25-25

=0.

单项选择题
单项选择题